The 8x zoom telescope lens with crystal back case is magic for Iphone 4 / 4S. It instantly converts your Iphone 4 / 4S into a telescope. It runs of rays effectively avoiding the contortion of image. And it makes the super wide angle the larger luminous flux the higher visual acuteness good for color reduction which makes the high quality of photography. Via the useful telescope lens you can play with the focus ring to get the best quality picture. It is a very good accessory for your Iphone 4 / 4S.